Euxenite-(Y) is an oxyde of niobium with tantalum and titanium and Rare Earth Elements (REE), with some calcium and radioactive elements like uranium or thorium. These elements give it a radioactive activity. This specimen we offer you is a cluster of parallel growth crystals, well-formed, with a chisel termination.With the classic ocher patina. It shows an adhered numerical label reading #439, and the classic label from Z. Gabelica (Belgium) has been preserved. A good chance to get this rare species.

95 €

Buy

This specimen is a recently discovered species from the pegmatites of Madagascar. It is a beryllium, lithium, and aluminium borate, LiAl₄Be₄(B₁₁Be)O₂₈. The specimen we offer exhibits several crystals with dodecahedral faces, good luster, and the characteristic milky-white color, aesthetically disposed on an elbaite crystal that reveals green and reddish hues under transmitted light. A top-quality miniature.

This new species can be confused with other minerals such as londonite or rhodizite, which are also found in this pegmatite. SEM-EDS analyses of these crystals confirmed the presence of K and Cs only in minor amounts, consistent with the empirical analytical results reported for the type material. You can consult the abstract of the preliminary publication by Hatert, F. et al. in The Canadian Journal of Mineralogy and Petrology (2025) 63 (6): 867–878 (https://doi.org/10.3749/250007). Analytical results will be provided to the buyer.

115 €

Buy

This specimen is a recently discovered species from the pegmatites of Madagascar. It is a beryllium, lithium, and aluminium borate, LiAl₄Be₄(B₁₁Be)O₂₈. The specimen we offer exhibits several crystals with dodecahedral faces, good luster, and the characteristic milky-white color. A top-quality piece of good size, featuring well-defined crystals.

This new species can be confused with other minerals such as londonite or rhodizite, which are also found in this pegmatite. SEM-EDS analyses of these crystals confirmed the presence of K and Cs only in minor amounts, consistent with the empirical analytical results reported for the type material. You can consult the abstract of the preliminary publication by Hatert, F. et al. in The Canadian Journal of Mineralogy and Petrology (2025) 63 (6): 867–878 (https://doi.org/10.3749/250007). Analytical results will be provided to the buyer.

Reserved

Group of betafite crystals showing defined octahedral faces (triangular), with axial growth. Very interesting for its crystallography and species. An oldie, classic and representative for the species. Although the term betafite was discredited in 2010, many of us still are using this term to define this mineral when we see it. Our specimen is an uranium, calcium, titanium and niobium/tantalum oxide with radioactive activity. Currently the betafite is included as a variety within the pyrochlore supergroup. As a note, the rich uranium term has been only found in the Moon (oxyuranobetafite).

A huge size crystal of betafite showing defined octahedral faces (triangular) and developed dodecahedral ones. Very interesting for its crystallography and species. An oldie, classic and representative for the species.
Although the term betafite was discredited in 2010, many of us still are using this term to define this mineral when we see it. Our specimen is an uranium, calcium, titanium and niobium/tantalum oxide with radioactive activity. Currently the betafite is included as a variety within the pyrochlore supergroup. As a note, the rich uranium term has been only found in the Moon (oxyuranobetafite).

ATTENTION: This sample will only be sent to buyers within the Iberian Peninsula or collect personally.

A huge size crystal of betafite showing defined octahedral faces (triangular) and developed dodecahedral ones. Very interesting for its crystallography and species. An oldie, classic and representative for the species.
Although the term betafite was discredited in 2010, many of us still are using this term to define this mineral when we see it. Our specimen is an uranium, calcium, titanium and niobium/tantalum oxide with radioactive activity. Currently the betafite is included as a variety within the pyrochlore supergroup. As a note, the rich uranium term has been only found in the Moon (oxyuranobetafite).

An old specimen collected in the 50s by L. Gautron in the pegmatite dikes those are located about 20 km SW of the city of Antsirabé, in the main highland of Madagascar. It is a euxenite-(Y) crystal showing defined faces and rounded edges, with good size. A historical specimen.

Group of microcline crystals, amazonite variety, showing defined faces. They are embedded in a matrix of feldspar and smoky quartz. The color is good and very attractive.

Sized elbaite-liddicoatite crystal, well defined, very aerial disposed, intense bourdeos red color, visible on the transparencies. It shows a striated prism faces with defines rhombohedral top faces. It shows a small dent that does not affect the aesthetics. On a feldspar matrix with sharp londonite crystals.

Euxenite-(Y) is an uncommon oxyde of niobium with tantalum and titanium and Rare Earth Elements (REE), with some calcium and radioactive elements like uranium or thorium. These elements give it a radioactive activity. This specimen we offer you is a cluster of parallel growth crystals, well-formed, with a chisel termination.With the classic ocher patina. A good chance to get this rare species.

Sold

A huge size crystal of betafite showing defined octahedral faces (triangular) and developed dodecahedral ones. Very interesting for its crystallography and species. An oldie, classic and representative for the species. This specimen belonged to the collection of P. Sainfeld, mineralogist at the École des Mines de Paris.
Although the term betafite was discredited in 2010, many of us still are using this term to define this mineral when we see it. Our specimen is an uranium, calcium, titanium and niobium/tantalum oxide with radioactive activity. Currently the betafite is included as a variety within the pyrochlore supergroup. As a note, the rich uranium term has been only found in the Moon (oxyuranobetafite).

Sold